Apple's iPad sailed through 2010 without much opposition as a worthy competitor from the Android or Windows camp failed to emerge to challenge its hegemony.

Post CES 2011, Apple will be launching its next edition of iPad in a very different landscape, no more a virgin territory but a landscape altered by the launch of multiple tablets by the likes of Motorola, Notion Ink Adam, RIM, LG, HTC, LG, HP and Samsung.

As manufacturers crafting these tablets differ, so is the underlying operating system. Earlier the iOS 4.2 running iPad had to fend off only Android but now it has to match HP's webOS, Google's tablet specific OS Android 3.0 (Honeycomb), Windows 7 and BlackBerry maker RIM's QNX.

Apple had the first mover advantage with iPad but the advantage is eroding and the tablet territory is crowded. It was Apple that set the benchmark for tablets in 2010 but the question is whether it will offer a repeat performance with iPad 2. What follows are the top 5 tablets released since CES 2011 which include Motorola Xoom, Notion Ink Adam, HP's TouchPad, LG's G-Slate and Samsung's Galaxy Tab 10.1 which Apple iPad 2 has to contend with: